As is known, detector modules of this type have a module housing having at least one electrical and at least one optical bushing, at least one electrical assembly connected to the electrical bushing, and at least one optical assembly connected to the optical bushing, the electrical and optical assemblies being arranged within the module housing, the optical and electrical assemblies being connected to one another via at least one optical interface, and the electrical assembly having at least one photodiode for converting the optical output signals of the optical assembly into electrical signals.
During the transmission of high-bit-rate data signals by means of higher-order modulation formats such as, e.g. D(Q)PSK, (DP)QPSK, n-QAM etc., the information coded in the amplitude and phase of the optical signal is converted into pure optical amplitude signals by means of an optical assembly, which are then converted into electrical signals by the electrical assembly and the photodiodes contained therein. One important point in the development and production of small and cost-effective components such as counterparts of DSL modems in the switching center (so-called “linecards”) and transponders, for example, is the integration of the different functionalities in one housing. What is critical here primarily is that predefined housing heights must not be exceeded and the electrical radio-frequency bushings must have predefined heights that are predefined by other modules—such as an electrical demultiplexer for example—disposed downstream of the detector module. The maximum housing height corresponds to 8.5 mm, for example, for standard linecards and to 6.5 mm, for example, for small form factor (SFF) transponders. The predefined height for the electrical radio frequency bushings is 3.32 mm, for example, and is determined by the height of the radio frequency inputs of an electrical demultiplexer that has become established commercially (see e.g. Sierra Monolithics SMI4034 and SMI4036).